Roll on roofing tar. Called 'Torch On' in some places. About a meter wide and 1/4 to 3/8" thick, absolutely dry to the touch, has clear plastic on one side. Install with plastic covering upward and replace carpet on top of that. Looks like rubber sheeting, cuts with tin snips or knife. For corners or odd shape lumps or depressions in floor warm with a propane torch to soften and mold into place. You can melt two pieces and they will 'weld' together. I got all I needed for asking at a construction site for the roll ends. Roofers like to use single pieces where possible and chuck shorter lengths.

"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs

There is a site where many were compared. I can't find it now but I might have it aved at work. It was good, with some good testing, and many brands were tested. Sorry for the teaser, hopefully I can come through with a link.

I believe S15DET is referring to sound deadener showdown. Great read. This actually influenced the purchase of my sound deadener. I used tiles from second skin audio and bought the foam and mass loaded vinyl locally.

This was actually version 2. I had also read version 1 but can no longer find it. The guy who did the original comparison now sells his own products and has a lot of information on his site. http://www.sounddeadenershowdown.com/ Hope that helps.

For the last 9-10 years, Mercedes Benz has been using a 1/4" thick foam pad with cardboard on both sides of it (1/4" Foam, sandwiched between 2 layers of thin cardboard) as a sound deadener on the roof panels of their sedans. It is as light as a feather, and is commonly sold in the USA as Poster board. I've seen it sold in drug stores and art stores. It's never used in areas where it would get wet, such as a door, but would work well in a roof, or a 2 door 510's quarter panles, and it's a lot lighter than any stick-on tar like material. They glue it on with several 1/4" beads of windshield glue, but I think even a tough sealer that dries like rubber (not silicone) and has really good adhesion would work well too.

pmaknefob wrote:For the last 9-10 years, Mercedes Benz has been using a 1/4" thick foam pad with cardboard on both sides of it (1/4" Foam, sandwiched between 2 layers of thin cardboard) as a sound deadener on the roof panels of their sedans. It is as light as a feather, and is commonly sold in the USA as Poster board. I've seen it sold in drug stores and art stores. It's never used in areas where it would get wet, such as a door, but would work well in a roof, or a 2 door 510's quarter panles, and it's a lot lighter than any stick-on tar like material. They glue it on with several 1/4" beads of windshield glue, but I think even a tough sealer that dries like rubber (not silicone) and has really good adhesion would work well too.